diff --git a/lib/src/engine/socket.dart b/lib/src/engine/socket.dart
index 7bfdd57..01e5396 100644
--- a/lib/src/engine/socket.dart
+++ b/lib/src/engine/socket.dart
@@ -73,6 +73,7 @@ class Socket extends EventEmitter {
   Transport transport;
   bool supportsBinary;
   bool upgrading;
+  Map extraHeaders;
 
   Socket(String uri, Map opts) {
     opts = opts ?? <dynamic, dynamic>{};
@@ -137,6 +138,7 @@ class Socket extends EventEmitter {
         this.perMessageDeflate['threshold'] = 1024;
     }
 
+    this.extraHeaders = opts['extraHeaders'] ?? {};
     // SSL options for Node.js client
 //  this.pfx = opts.pfx || null;
 //  this.key = opts.key || null;
@@ -239,7 +241,7 @@ class Socket extends EventEmitter {
 //  'rejectUnauthorized: options.rejectUnauthorized || this.rejectUnauthorized,
       'perMessageDeflate':
           options['perMessageDeflate'] ?? this.perMessageDeflate,
-//  'extraHeaders: options['extraHeaders ?? this.extraHeaders,
+      'extraHeaders': options['extraHeaders'] ?? this.extraHeaders,
 //  'forceNode: options.forceNode || this.forceNode,
 //  'localAddress: options.localAddress || this.localAddress,
       'requestTimeout': options['requestTimeout'] ?? this.requestTimeout,
diff --git a/lib/src/engine/transport/io_websocket_transport.dart b/lib/src/engine/transport/io_websocket_transport.dart
index 5f488f4..5ce55b4 100644
--- a/lib/src/engine/transport/io_websocket_transport.dart
+++ b/lib/src/engine/transport/io_websocket_transport.dart
@@ -1,4 +1,4 @@
-// Copyright (C) 2019 Potix Corporation. All Rights Reserved 
+// Copyright (C) 2019 Potix Corporation. All Rights Reserved
 // History: 2019-01-21 12:13
 // Author: jumperchen<jumperchen@potix.com>
 
@@ -19,6 +19,7 @@ class IOWebSocketTransport extends Transport {
 
   bool supportsBinary;
   Map perMessageDeflate;
+  Map extraHeaders;
   WebSocket ws;
 
   IOWebSocketTransport(Map opts) : super(opts) {
@@ -26,6 +27,7 @@ class IOWebSocketTransport extends Transport {
     this.supportsBinary = !forceBase64;
     this.perMessageDeflate = opts['perMessageDeflate'];
     this.protocols = opts['protocols'];
+    this.extraHeaders = opts['extraHeaders'];
   }
 
   void doOpen() async {
@@ -33,7 +35,7 @@ class IOWebSocketTransport extends Transport {
     var protocols = this.protocols;
 
     try {
-      this.ws = await WebSocket.connect(uri, protocols: protocols);
+      this.ws = await WebSocket.connect(uri, protocols: protocols, headers: extraHeaders);
     } catch (err) {
       return this.emit('error', err);
     }
diff --git a/test/io_client.dart b/test/io_client.dart
index f95248a..63d57cb 100644
--- a/test/io_client.dart
+++ b/test/io_client.dart
@@ -1,11 +1,14 @@
-// Copyright (C) 2019 Potix Corporation. All Rights Reserved 
+// Copyright (C) 2019 Potix Corporation. All Rights Reserved
 // History: 2019-01-21 11:56
 // Author: jumperchen<jumperchen@potix.com>
 import 'dart:async';
 import 'package:socket_io_client/socket_io_client.dart' as IO;
 
 main() {
-  IO.Socket socket = IO.io('http://localhost:3000', <String, dynamic>{'transports': ['websocket']});
+  IO.Socket socket = IO.io('http://localhost:3000', <String, dynamic>{
+    'transports': ['websocket'],
+    'extraHeaders': {'foo': 'bar'}
+  });
   socket.on('connect', (_) {
     print('connect');
     socket.emit('msg', 'init');
diff --git a/test/server.dart b/test/server.dart
index 56fc774..bb52f8e 100644
--- a/test/server.dart
+++ b/test/server.dart
@@ -16,6 +16,9 @@ main() {
   // Dart server
   var io = new Server();
   io.on('connection', (client) {
+    final headers = client.handshake['headers'];
+    headers.forEach((k, v) => print('$k => $v'));
+
     print('connection default namespace');
     client.on('msg', (data) {
       print('data from default => $data');